2D/3D switchable stereoscopic display device

• US 9,786,232 B2
• Filed: 08/20/2015
• Issued: 10/10/2017
• Est. Priority Date: 09/02/2014
• Status: Active Grant

• Current Assignee: Superb Technology Co Ltd
• Original Assignee: Superd Co., Ltd.
• Inventors: Quan, Hongwei, Pi, Jiajia, Guo, Fuzhong, Gong, Xiaoda
• Primary Examiner(s): Nguyen, Sang V
• Application Number:
  US14/831,458
• Publication Number:
  US 20160065950A1
• Time in Patent Office: 782 Days
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: G02B 30/28 involving active lenticular arrays
• CPC Class Codes: G02F 1/13306 Circuit arrangements or driving methods for the control of single liquid crystal cells G02F1/132, G02F1/133382 take precedence
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/13398 Spacer materials; Spacer properties
• CPC Class Codes: G02F 1/292 by controlled diffraction or phased-array beam steering controlled diffraction for optical switching G02F1/31
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: H04N 13/305 using lenticular lenses, e.g. arrangements of cylindrical lenses
• CPC Class Codes: H04N 13/356 having separate monoscopic and stereoscopic modes

Abstract

A stereoscopic display device includes a display panel for displaying 2D/3D images, a driving circuit module, and a light-splitting device. The light-splitting device includes a first substrate having a plurality of first electrodes, a second substrate arranged facing the first substrate and having at least one second electrode, a liquid crystal layer placed between the first substrate and the second substrate, and a plurality of spacers in the liquid crystal layer. The driving circuit module is configured to, when in the 3D display mode, provide a plurality of driving voltages between the first electrodes and the second electrode to make the liquid crystal layer an array of liquid crystal lenses and, when in the 2D display mode, to provide a deflection voltage between the first electrodes and the second electrode to reduce a refractive index difference between the liquid crystal molecules and the spacers with a predetermined range.

Claims

1. A stereoscopic display device, comprising:

a display panel for displaying 2D images and 3D images;

a driving circuit module; and

a light-splitting device coupled to the display panel to separate light emitted from the display panel displaying the 3D images to effect 3D display effect in a 3D display mode and to pass through light emitted from the display panel in a 2D display mode,

wherein the light-splitting device includes;

a first substrate having a plurality of first electrodes;

a second substrate arranged facing the first substrate and having at least one second electrode;

a liquid crystal layer placed between the first substrate and the second substrate and containing liquid crystal molecules; and

a plurality of spacers placed between the first substrate and the second substrate and in the liquid crystal layer to support a thickness of the liquid crystal layer; and

wherein the driving circuit module is configured to;

when in the 3D display mode, provide a plurality of driving voltages between the first electrodes and the second electrode to make the liquid crystal layer an array of liquid crystal lenses;

when in the 2D display mode, provide a deflection voltage between the first electrodes and the second electrode to reduce a refractive index difference between the liquid crystal molecules adjacent to a spacer and the spacer within a predetermined range, thereby reducing light refraction between the liquid crystal molecules and the adjacent spacer, wherein the predetermined range of the refractive index difference between the liquid crystal molecules adjacent to the spacer and the spacer is less than 0.1,

wherein;

an alignment direction of the liquid crystal layer is horizontal;

an angle between an extending direction of the second electrode and the alignment direction of the liquid crystal layer is an acute angle;

in the 2D display mode, the deflection voltage produces a horizontal electric field between the first substrate and the second substrate; and

an angle between the extending direction of the second electrodes and the alignment direction of the liquid crystal layer is 45°

or slightly greater than 45°

corresponding to a desired range of the deflection voltage for maintaining an electric field.

2. The stereoscopic display device of claim 1, further comprising:

a voltage module providing an initial voltage to the driving circuit module,

wherein the driving circuit module is configured to;

when in the 3D display mode, convert the initial voltage into the plurality of driving voltages; and

when in the 2D display mode, convert the initial voltage into the deflection voltage.

3. The stereoscopic display device of claim 1, wherein:

the deflection voltage is greater than a threshold voltage of the liquid crystal molecules and smaller than or equal to the initial voltage.

4. The stereoscopic display device of claim 1, wherein:

the refractive index difference between the liquid crystal molecules and the spacer is a difference between a refractive index of the liquid crystal molecules rotating at an angle under the deflection voltage and a refractive index of the adjacent spacer.

5. The stereoscopic display device of claim 1, wherein:

the first electrodes are strip-shaped electrodes arranged in parallel; and

the second electrode is a plane-shaped electrode.

6. The stereoscopic display device of claim 1, wherein:

the first electrodes are strip-shaped electrodes arranged in parallel; and

the at least one second electrode includes a plurality of strip-shaped electrodes arranged in parallel.

7. The stereoscopic display device of claim 2, wherein:

the driving circuit module includes a signal generation module and a voltage switching module; and

when in the 2D display mode, the signal generation module produces a control signal to control the voltage switching module to switch output of the driving circuit module from the driving voltages to the defection voltage.

8. The stereoscopic display device of claim 7, wherein:

the voltage switching module includes a switching unit; and

the switching unit receives the control signal to switch the driving voltages to the deflection voltage.

9. The stereoscopic display device of claim 8, wherein:

the voltage switching module includes a voltage adjusting unit;

the voltage adjusting unit is electrically connected in series to the output of the voltage module to adjust the driving voltages; and

the voltage adjusting unit is electrically connected in parallel to the switching unit.

10. The stereoscopic display device of claim 9, wherein:

the voltage switching module further includes a voltage regulating unit to regulate the driving voltages and the deflection voltage;

the voltage regulating unit is electrically connected in series to the voltage adjusting unit; and

outputs of the voltage regulating unit are electrically connected to the first electrodes and the second electrodes.

11. The stereoscopic display device of claim 7, further comprising a detection module, wherein:

the detection module is configured to detect whether a viewer is within a predetermined viewing range of the 3D display mode, and the predetermined viewing range refers to a plurality of discrete suitable viewing distances determined by a plurality of discrete light separation unit widths, and the viewer has a desired 3D viewing experience of the stereoscopic display device in the predetermined viewing range; and

when the viewer is not in the predetermined viewing range of the 3D display mode, the detection module sends a detection signal to the driving circuit module to generate the control signal for the 2D display mode.

12. The stereoscopic display device of claim 2, wherein:

when in the 2D display mode, the voltage module, through the driving circuit module, supplies a first voltage to the first electrodes and a second voltage to the second electrode; and

a difference between the first voltage and the second voltage is the deflection voltage.

13. The stereoscopic display device of claim 2, wherein:

the liquid crystal molecules in the liquid crystal layer rotate at various angles in the horizontal electric field.

14. The stereoscopic display device of claim 13, wherein:

the horizontal electric field at intersections of the first electrodes and the second electrode is a strong electric field;

a rotation angle of the liquid crystal molecules in the strong electric field region is n₁; and

a rotation angle of the liquid crystal molecules away from the strong electric field regions is n₂, n₁>

n₂.

15. The stereoscopic display device of claim 13, wherein:

the liquid crystal molecules in the strong electric field rotate at an angle toward a first direction; and

the first direction is perpendicular to the extending direction of the second electrode.

16. The stereoscopic display device of claim 13, wherein:

the first voltages are a ground;

the second voltages are AC voltages; and

any two adjacent second electrodes are supplied with two AC voltages with opposite phases and identical amplitudes.

17. The stereoscopic display device of claim 13, wherein:

an angle between the extending direction of the first electrodes and an extending direction of the second electrodes is α

₁, α

₁ being an acute angle.